Many work machines in the earth-moving and agricultural industries such as, for example, large mining trucks and large off-highway trucks, may include hydraulic braking systems that are associated with hydraulic hoist systems. In such work machines, a hoist valve of the hydraulic hoist system may be in fluid communication with a brake cooling circuit of the hydraulic braking system. In some arrangements, the hoist valve may provide a fluid path to the brake cooling circuit so that the hydraulic fluid may cool the braking system of the work machine. During a hoist raise command, the fluid flow from the rod end of the hoist valve may be dumped to the brake cooling circuit. While such an arrangement is effective for cooling the brake pads, the brake cooling circuit may experience transient pressure spikes such as those caused by the large fluid flow from the rod end of the hoist valve to the brake cooling circuit when the hoist valve is commanded to be in the raised position. These transient pressure spikes may compromise the duo cone seals in the brake cooling circuit causing an external leak point for the hydraulic fluid to the rear axle of the work machine.
U.S. Pat. No. 4,271,937 (the '937 patent) discloses valves for hydraulic brakes. While the '937 patent teaches a valve that may provide a flow path in a brake cooling circuit to cool hydraulically-operable rotary friction brakes, it fails to teach a valve in association with a hydraulic hoist system and, thus, also fails to teach a valve that reduces or eliminates transient pressure spikes resulting from large fluid flow changes to the brake cooling circuit such as those transient pressure spikes caused when a hoist valve of the hydraulic hoist system is commanded to be in a raised position.